Determining connectivity of organisms is difficult especially for early life history stages (larvae and juveniles). Fortunately, a variety of natural and artificial tags, some of which date back to the 1600’s, have been developed to help address the issues of movement. Over the years a vast literature on tagging has emerged, of which I provide an updated review. In this chapter, I discuss five broad areas of tagging (external tags, external marks, internal tags, telemetry, and natural tags) and provide additional information on genetic and chemical methods. For each method I highlight their advantages and disadvantages, and provide examples, where possible, of connectivity among tropical coastal ecosystems. Advances in many of the methodologies are expected to continue, and future studies should consider combining more than one approach especially where natural tags are utilized